As is known, an intercepting valve comprises a valve body and a obturator situated inside it which, when the valve is in the closed position, shuts off transit through the valve body to prevent the transit of fluid through the valve, and, in the open position, allows the transit of fluid.
In various rotated positions of the obturator, between the closed position and the open position, the valve body presents an opening for transit, the shape and extension of which influence the flow and/or pressure characteristics of the fluid coming out downstream of the valve body.
Many embodiments of valves have a shaped obturator so that the opening produced in the various rotated positions of the obturator is such that the fluid has the desired flow and/or pressure characteristics downstream of the valve body.
In the specialist language used in this sector it is said that the fluid has the desired characterisation depending on the rotation of the obturator.
For example, an embodiment and a method of fabrication of a shaped obturator are shown in the Italian patent application for invention BS2006A000061, in the Applicant's name.
The valves produced in such manner however have the negative feature of being designed to give the fluid certain characteristics and cannot satisfy the requirements of users requiring a different characterisation.
Sometimes, in order to resolve this shortcoming, the obturator is fabricated in the traditional manner, that is without any shaped opening to produce a certain characterisation and, downstream of the obturator, an obstructive element is mounted in the valve body which influences the fluid so as to give it certain characteristics.
An example in such sense is shown in the Italian patent application for invention BS2005A000076, in the Applicant's name.
The valves produced as described above however have the disadvantage of having higher manufacturing costs due to the production of the components and their assembly.